Ladder



A. BIANCHI Jan. 16, 1951 LADDER 4 Sheets-Sheet 2 Filed May 6, 1946 INVENTOR. AMBROSE B/NCH' BY W A7' TORNEV `km. 16, 1951 A. BlANcl-u 2538501 LADDER Filed May 6, 1946 I 4 Sheets-Sheet 3 INVENTOR. AMBROSE B/ANCH/ ATTORNEY.

A. BIANCH! Jan. 16, 1951 LADDER 4 Sheets-Sheet 4 Filed May 6, 1946 INVENTOR.

ATTORNEY.

AMBROSE B/A/VGH/ Patented Jan. 16, 1951 UNITED 'vsrA'rE/s PAITE-NT AOFFICE:

i Ambrose Bianchi, San Francisco, Calif.

Application May 6', 1946, Serial No. 66755751 This invention relates to `;step ladders of the foldingltypein which a rung portionzand a prop portion :are hinged together so that they may be folded to occupy 'less'space "whenstored lor transported than when in use. The prop portion referred to includes two supporting legs spread apart inldivergent -relation from top `to bottom to Vstabilizre theladder when it is in use. =ne of the objects of `my invention is to pro- 'vide a folding ladder, vthe rung por-tion and the prop portion of which may beextended and collapsed in .the ldirection of their lengths, vso that not .only may. the vladder vbe stored rand .transported in'sma'll spaces, `but it may be used in places having comparatively .little or great verv.tical clearance or. headroom. Another of the objects of my invention is to provide, in a ladder having diverging legs in the' than the extended length of the prop legs so that the rung portion can have footing 'on a 'higher step and the prop legs can 'be extended to footings on Steps lower than the footings of the rung `portion. In this 'way the ladder can be approached from the head end of a fiight of .stairs andthe ladder can be used on flights having relatively low ceilings. i i t These and other objects -and advantages are attainecl by the construction and arrangement ,of parts as described 'in the following specification wherein reference is made to 'the accompanying drawings, in which:V

Fig. V1 is an isometric view of my new ladder showing the leg Sections and the rung Sections fully extended;

' Fig. .2 is a view of 'the front of thev iadder with i the run'g and prop Sections in vfully collapsed relation and :the rung portion and prop 1eg`s folded i `together so that the ladder occupies a minimum of space; a

F-igs. l3 and 4 are elevations of the supporting leg vSections in fully extended and collapsed re- 'lations .respective'1y;

' j'g. Vfiat 'is an enlarged fragmentary view of a 2 claims. (cl; 228-721) Figs. 4b and 40 are fragmentary Sections at IVb-IVb and IVc-IVc respectively, of Fig. 4;

Figs. l5, 6 and 7 Villustrate details of the telescoping members 'employed' in 'both the -leg sectionsand the rung'sections;

Figs. 8 through 12v, inclusive, are diagrammaticviews illustrating the construction, and the'various -phases of the operation, of the elements governing the extension and collapsing of 'the rung sections'in extended relation; and

Fig. 13 vis .a similar Vview illustrating the construction vand operation of the elements governing .the extension .and collapse of the prop 'section. The :ladder shown in the -drawings comprise's a rung portion li! and a supporting vprop Dortion L2., hinged for folding 'and unfolding to a Vplatform 'M by pivot screws and hinge 18 (Fig. 3'). Untoldi-ng :or spreading of the prop and rung portons is limited by a folding linkage |5 well known in the art. .The pivot screws 16 extend through angle ,brackets V20, secured to platform M by screws 22, and into the wood of upper prop Sections 38.. Hinging at 'l- Vmay 'be 'provided by a conventional T hinge, the bar 2.5 of which is securely fastened to the platform Id and the strap "28 being provided with a Vertical slot '30 in which Va pin 32 is :free toslide. Pin 32 pivotally connects braces ;3'4 of the upper prop seci tions 38 which are pivoted at their lower ends as 'shown at 36 in Fig. 4. The prop Sections 13.8 diverge downwardly as shown and are provided on Vtheir outer sides with longitudinal metal rails Lin -forming a part of the telescoping mechanisml of the prop.

The lower part of the' supporting prop is formed by the prop members 62 joined near their` lower extremities by the cross bar 44 centrally provided 'with a Vertical slot 1362 .(Fig.. 4a) in which za pin 48 'pivotally connecting the bra'ccs 5l is free to slide. Braces 59 are pivoted as at 52 at their upper ends. 'The telescopic rails 40 on the upper leg section P38 are received in telescopic Channels 54 in the lower prop sections '42 '(see'Fig. 5). 'Meansto -be described govern the operation of these telescoping members.

The pivotallinkages of the braces 34 at 32 and braces 5!! at 158 permit :the divergent legsito 'tele'- scopica'lly slide with completeV freedom, the sliding downwardly'of pin 48 in slot 46 accompanying the movement of leg stringers 38 downwardly because `vthis movement draws the upper ends of leg stringers 652 closer together. In the same movemen'tfthe lower ends of 'leg stringer'sections ing with angled bracket portions 810 two longitudinal slide bearing grooves 3'ld inA which there are reciprocatively received the longitudinally extensible bearing portions 6 ia of a channel strip 88.

secured by screws 63 to prop member 42 with the channel interlock housing part lb'received by a longitudinal groove 6|c in member .42.` The interlockhousing parts Gib `includes longitudinal side wa'ls 82 and 12 provided with dog control ports', as at 14 and receives the rail portion 48 to bemore speciflcally described later.

The plate forming rail 48 and the bottom 6|d of the housing Slb are spaced apart to provide a space 68 within which dogs carried by rail 40. for Cooperation with openings T4 are disposed as will presently be' described in detail. The interlocking arrangernent provided within' the channel and associated' with space 63 (Fig. 5) for both the prop and the rung portions of the ladder are explained with the aid of Figs. 8 through 13, in which forvFig. 18 only the side walls '92 and 12 of the housing V61 b, and portions of the rail 4-53 with dogs,etc., are shown, and for Figs through 12 the corresponding side walls 62' and 12 and rail 48' with its dogs are shown.

The rung portion I 0 of the ladder comprises, as shown in Fig. 1. a series of telescopically interengaged Sections 18, 88, 82 and 84. The Sections 18, 89 and 82 each include a single horizontal' rung 18a, 88a,'and 82a, respectively, extending between parallel ladder-leg Sections 18D, 881) and The top section 84 may be provided with two or more rung sections 84a and supports the platform l4.

The Sections 18 to 84 telescope with relation to each other to enable them to slide to the compact positions illustrated in Fig. 2.

The telescoping members are connected by railsand Channels constructed as shown in Figs. 5, 6 and 7 as previously described and in association therewith there are certain latching elements determining the manner of holding and releasing the rung Sections for extension'and colillustrated in Figs. 8 through 12 in which the rail 48' is shown in several positions as it slides between the walls 12 of the channel.

Fig. 8 shows the positions assumed by the parts when the rung Sections of the ladder are collapsed. Consider the rail 40' as the moving member and the channel as fixed. A dog 88 pivoted to the rail 46' will upon slight movement of the rail (leftward in Fig. 8) be released for c'ounterclockwise rotation about its pivot 88 as its heelv 98 comes in registry with hole 92. Toe 94 remains engaged in hole 96 until by further movement dog 86 is rotated to the position shown in Fig. 9, and toe 94 is drawn out of hole 96 against theclockwise urgency of spring 98. In this relation the rail 40 and dog 86 travel until stopped in the over-extended position illustrated in Fig. 10 by the over-extension-stop Vdog |88 which engages the edge. |82 of a hole |06 suitably located for the purpose. Dog 85 remains in this position with its toe 94' biased against wall 62' until the movement of V'raillllll' is reversed slufliciently to permit toe 94 to fall into hole 184.

latching mechanism will be facilitated by a dee scription of its function. In extending section 84 with respect to section 82, the extension is to a length greater than the actual separation when in position for use. After' such over-extension, section 84 is permitted to fall back into the position for use, in which it is automatically retained by looking dogs hereafter'described. These dogs serve their holding function until the section 84 is required to be collapsed', which is accomplished by firstextending section 84 from section 82 as This effects the release of the With this, further continued movement in reverse or collapsing direction lof the rail 48 is prevented and the two sections of ladder rungs are now in usable extended relation, held so by the dog 88 in holes 94. v

g Incident to this short reverse movement, the dog [68 is caused to rotate about its pin 188 and slot pivot IM on rail 49' and to reverse its position, through its engagement with the edge of the dog stop and reversing hole 106, so that in the usable position of Fig. 12, dog IO!! is held inactive by'the inside surface of wall 12' upon which it slides, being urged clockwise about pin |88'by tension spring I fl.

To release the rail 48' for movement rightward moved to the left to a position as in Fig. 12, beyond that of Fig.'lO, where the toe 94 of dog 86 entersV dog release opening v| 12 and the rail 48' is stopped by fixed stop ||4. Dog 188 in this movement'slides over opening' |86, its straight back ia engaging with wall 12'. In the Fig. 12 position, dog enters release hole I l2 and, upon thenextrightward movement of rail 48' dog 86 is' permitted toerotate to the position of Fig. 12 under action of spring 98, and to be further rotated clockwise incident to rightward movement when the toe 94 engages the rightward edge of opening ||2, the rotation being timed and sufiicient to'cause the dog .to clear the right edge of clearance opening U4. The dog 88` is then held in a position relative to rail 48 similar to that shown inV Fig. 8 until again reversed slightly leftward of the Fig. 8 position as previously described. The over-extension stop dog |08 remains in the same relative position from` the Fig. 12 to the Fig. 8 positions', remaining inoperative until, in moving'from the Fig. 8 position toward the overextended position of Fig. 10, it is reversed to opera'tve position when its hook end IIS is biased by spring i IO outwardly through hole |4 and engages the camming surface ||8 of hole ||4.

`. .The prop members 38-may be extended inA any desired degree and maintained in such condition of extension against collapse by dogs 56 (Fig. 13) pivoted by pins 58 secured on the lower (as shown in Fig. 5) surface of the rail 48 within the portion 83 of channel space 54 formed by channel memberll. The side walls 62 of 'the channels are provided through the greater portions'of their lengths with a series of equally spaced op'enings 64 disposed adjacent the path of movement of the dog 5,6 as shown in Fig. 13 so that when the dog 56 is in the position shown its engaging tooth 66 is drawn into the corresponding opening 64 by the spring 68 and the rail 40 and leg 38 cannot be moved (rightward in Fig. 13) in the direction of collapse. Thus, the Vholes 64 and dog 56 provide for holding the legs against collapse in any desired position of adjustment.

Provision is made so that when the ladder is in a partially extended position it may be readjusted to a less extended position, but this may only be done deliberately because the heel of the dog engages the Wall 12 of the channel and is prevented from rotating to released position. When the rail 40 has moved leftward (in Fig. 13) into the last hole 64' the rail 40 may be returned to collapsed position. The wall 12 is provided with a release opening 14 opposite a dog engaging and reversing hole 64' so that upon urging the rail 40 rightwardly (in Fig. 13) the dog 56 is turned clockwise about pin 59 so that the tooth 66 is disposed in trailing relation to pin 58 and rides over the holes 54. The leg sections must be fully collapsed before the dog 56 again becomes eifective; that is, before it may return to the full line position of Fig. 13. This is effected when the dog has moved to a collapsed position opposite a second dog engaging and reversing hole 64" in registry with which there is provided an elongated dog-olearance hole 16 in the wall 12, by the action of spring 68 which turns the dog 56 counterclockwise about 58 to the normal position (full line position of Fig. 13). It will be evident, therefore, that the shortening of the ex'- tended prop legs requires first a full extension of the legs, a return to the fully collapsed state and a readjustment to the required shorter length. In this way it is insured that the legs cannot be collapsed While the user is on the ladder, the olearance hole 14 being substantially beyond the range of ladder use, which use corresponds to the extent of the holes 64.

With the construction just described, the rung i extended. Thus, with the ladder shown, four different ladder lengths are provided, and the supporting legs l2 can be adjusted to any length greater than its minimum length to accommodate the ladder to inclined footing.

I claim:

1. In a ladder having a platform, and having a telescopic ladder section and a prop portion supporting the platform, said prop portion having telescoping sets of downwardly diverging legs, means for bracing said legs relative to each other comprising a brace pivotally connected to each leg part at one end and pivotally and slidably connected to a fixed ladder part at its opposite end.

2. In a ladder having a platform, and having a telescopic ladder section and a prop portion supporting the platform, said prop portion having telescoping sets of downwardly diverging legs, means for bracing said legs relative to each other comprising a pair of angularly related braces pivotally connected one with each of the upper leg parts and slidably and pivotally connected to the platform, a horizontal brace extending between the lower leg parts, and angular braces pivoted one to each lower leg part and slidably and pivotally connected with said horizontal brace.

AMBROSE BIANCI-H.

REFERENCES CITED The following references are of record in the fileof-.this patent:

UNITED STATES PATENTS Kostuk Mar. 26, 1940 

